Lid for a manifold

ABSTRACT

A lid for a distribution manifold is described where the manifold has an inlet opening defining an axis, access opening opposite the inlet and a plurality of radially extending outlet ports. The lid for the access opening includes a mounting member adapted to couple the lid to the manifold to close the access opening, a cone coupled to the mounting member and extending axially toward the inlet opening of the manifold when the lid is coupled to the manifold, and a single piece retainer adapted to secure the cone to the mounting member without additional fasteners.

DETAILED DESCRIPTION

A manifold and distribution manifold assembly consisting of the manifoldand a lid is provided and described below. The distribution manifoldassembly is used to divide the flow of an air-entrained material from aprimary distribution line into a plurality of secondary distributionlines. One application of such a distribution manifold assembly is in anagricultural air seeder.

In the figures,

FIG. 1 is a side elevation view of an agricultural air seeder;

FIG. 2 is a top perspective view of the manifold described herein;

FIG. 3 is a vertical sectional view of the manifold of FIG. 2;

FIG. 4 is a bottom perspective view of a lid of the distributionmanifold assembly described herein;

FIG. 5 is a vertical sectional view of the lid of FIG. 4;

FIG. 6 is a vertical sectional view of the distribution manifoldassembly described herein;

FIG. 7 is an enlarged view of the lid and manifold attaching structure;and

FIG. 8 is an exploded perspective view of the lid.

By way of example, with reference to FIG. 1, an air seeder 10 is showncomprising a seed cart 12 towed by a tractor (not shown) and a tillageimplement 14. The seed cart 12 has a frame 16 to which product tanks 18and wheels 20 are mounted. Each tank 18 has an associated meteringsystem 22 at its lower end (only one of which is shown) for controllingand feeding of product into a pneumatic distribution system 24 and aprimary manifold 26. The tillage implement 14, towed behind of the seedcart 12, consists generally of a frame 30 to which ground openers 32 aremounted. Incorporation of seed row finishing equipment such as closingwheels 34 is also desirable in many applications.

The pneumatic distribution system 24 includes a centrifugal fan 36connected to a plenum 38 which is in turn connected to one or moreprimary manifolds 26, each associated with a product tank 18. Theindividual passages in the primary manifolds 24 are each connected to aprimary distribution line 40 leading to a riser tube 42, only one ofwhich is shown. Each riser tube 42 is in turn coupled to a distributionmanifold assembly 44. Secondary distribution lines 46 connect thedistribution manifold assembly 44 to seed boots mounted to the groundopeners 32 to deliver product, seed, fertilizer, etc. to the furrowformed by the openers 32.

The manifold assembly 44 contains a manifold 50 and a lid 60. Manifold50 is molded as a single piece and includes an inlet opening 52 which iscylindrical in shape, defining an axis 54. Inlet opening 52 isconfigured to couple to the end of the riser tube 42 to receiveair-entrained material therefrom. The cylindrical shape of the inletopening facilitates the even distribution of the material to the outletsports described below, but other shapes can be used if desired. Oppositethe inlet opening 52, the manifold 50 has an access opening 56 formed byan axially extending cylindrical wall 58. The access opening 56 ispreferably larger than the inlet opening 52. Extending outwardly fromthe cylindrical wall 58 are a plurality of outlet ports 62. The outletports extending generally radially outwardly relative to the axis 54.The outlet ports are evenly spaced angularly about the manifold. Theoutlet ports 62 each receive a secondary distribution line 46 (FIG. 1)with the line of 46 inserted into the outlet ports 62. The exterior ofeach outlet port is formed with a recess or groove 64 in which a hoseclamp (not shown) is seated to secure the secondary distribution line 46in the outlet port 62. Typically, each outlet port 62 receives asecondary distribution line 46. However, if fewer secondary distributionlines are needed, some of the outlet ports 62 can be plugged. Troughs 66extend radially outward from the inlet opening 52 to each outlet port62. The troughs 66 are separated by raised ribs 68. A small step 70 islocated at the transition of the trough 66 to the interior of the outletport 62 to allow the inside of the secondary distribution lines 46 toform continuous surfaces from the troughs 66.

The lid 60 fits on to the manifold 50 to close the access opening 56.The lid includes an inner cone 72 and an outer mounting member 74. Thecone 72 is snap fit into the mounting member while the mounting memberattaches to the manifold 50. The cone has a lower wall 78 forming adownwardly projecting cone as shown in FIG. 5 forming a cone tip 79. Thewall 78 is slightly concave to complement the top surface of the ribs68. When the lid 60 is mounted on the manifold 50, the cone wall 78 ispositioned slightly above the top of the raised ribs 68. Alternatively,the wall 78 can engage the top of the ribs.

As described above, the manifold 50 is positioned on the riser tube 42with the riser tube 42 inserted into the opening 52 up to the step 76 atthe top of the opening 52. With the lid 60 on the manifold, a hollowcentral area 80 is formed in the interior of the manifold above theriser tube 42 and below the wall 78 of the cone. The hollow central area80 is generally in the center of the raised ribs 68.

The mounting member 74 has a top wall 82 and a pair of downwardlydepending annular walls, inner annular wall 84 and outer annular wall86. An annular groove 88 is formed between the walls 84, 86. An O-ring90 is placed in the groove 88. The outer annular wall 86 has a pluralityof slots 92 formed therein to receive projections 94 on the outer sideof the manifold cylindrical wall 58. The slots 92 have a generallyaxially extending entry portion 96 to receive the project 94. The lid isthen rotated about the axis to move the projection into acircumferentially extending portion 98 of the slot. When the lid isrotated, the projection moves over a retaining member 100 on one side ofthe slot which requires slight deformation of the wall 102 of themounting member 74. Once seated on the manifold, the lid 60 requires aminimum twisting force be applied to the lid to move the projection backto the entry portion 94 of the slot 92 to remove the lid. When the lidis seated on the manifold, the cylindrical wall 58 bears against anddeforms the O-ring 90 to create a seal between the manifold and the lidto prevent air leakage therebetween that would interfere with thetransport of material in the air stream.

The cone 72 is attached to the mounting member 74 by a retainer in theform of a cylindrical retaining ring 110. Cone 72 has a cylindrical wall112 having a radially outward extending lip 114 at its distal end 115,that is, the end of the cylindrical wall 112 distal to the cone tip 79.The cylindrical wall 112 is positioned inside the inner annular wall 84of the mounting member. The retaining ring 110 fits between the conecylindrical wall and the mounting member inner annular wall 84. Theretaining ring 110 bears against the lip 114 to hold the cone in place.The retaining ring includes outward projecting tabs 116 that snap fitinto grooves 118 in the inner annular wall 84 to hold the ring 110 inplace and attach the cone to the mounting member 74. Other than theretaining ring 110, no additional fasteners are used to coupled the coneto the mounting member. The mounting member top wall 82 and the cone 72define a hollow interior 122 of the lid. The hollow interior minimizesthe quantity of material used to mold the components of the lid. Themounting member is also formed with two integral handles 120 formanipulating the lid 60.

In one embodiment, the manifold 50 is formed by a compression moldingprocess. The material used for the manifold is a thermoset elastomer ora thermoplastic elastomer. One suitable material is EPDM with suitableUV stabilizers. The flexibility of the elastomer enables the outletports 62, in combination with the secondary distribution lines 46, toprovide a slight press fit engagement to help secure the secondary lines46 in the outlet ports. Furthermore the flexibility of the elastomerallows the outlet ports to be squeezed onto the secondary distributionline 46 by the hose clamps seated in the grooves 64. This provides asecure coupling of the secondary distribution lines in the respectiveoutlet ports. The use of an elastomer, together with a compressionmolding process, provides for a low-cost manifold when the tooling costand the piece cost are considered together for low volume production ofthe manifold. For higher volume production, an ejection molding process,using a thermoplastic urethane can be employed. The tooling cost ishigher, but the individual part cost is lower and thus better suited forhigher production volumes.

The cone 72 of the lid 60 is preferably formed of a thermoplasticpolyurethane. This provides the high wear resistance necessary for theimpact of the air entrained material. Such a material is relativelyexpensive. The mounting member 74, which need not have a high wearresistance, can be made of any rigid injection moldable material,preferably one that is inexpensive. The primary driver in the selectionof the material for the mounting member is the structural strength formounting the lid onto the manifold. A glass reinforced nylon iswell-suited to this application.

A distribution manifold assembly has been described for use in dividingthe flow of an air-entrained material from a primary distribution lineinto a plurality of secondary distribution lines. The manifold is formedof a single molded piece thereby reducing the overall tooling cost ascompared to manifolds assembled of multiple molded components. Oneapplication of such a distribution manifold assembly is in an airseeder.

Having described one or more embodiments, it will become apparent thatvarious modifications can be made without departing from the scope ofthe accompanying claims.

What is claimed is:
 1. A lid for a distribution manifold, the manifoldhaving an inlet opening defining an axis, access opening opposite theinlet and a plurality of radially extending outlet ports, the lidcomprising: a mounting member adapted to couple the lid to the manifoldto close the access opening, the mounting member haying a top wall and adownwardly depending inner annular wall; a cone coupled to the mountingmember and extending axially toward the inlet opening of the manifoldwhen the lid is coupled to the manifold, the cone haying a cone shapedwall forming a cone tip and a cylindrical wall disposed radially inwardfrom the inner annular wall of the mounting member; and a single pieceretainer adapted to secure the cone to the mounting member withoutadditional fasteners, the retainer being a cylindrical ring positionedbetween the inner annular wall of the mounting member and thecylindrical wall of the cone and adapted to secure the cone to themounting member.
 2. The lid as defined by claim 1 wherein the cone andmounting member define a hollow interior.
 3. The lid as defined by claim1 wherein the cone cylindrical wall has a lip at a distal end thereoftrapped by the retaining ring to hold the cone in place relative to themounting member.
 4. The lid as defined by claim 1 wherein the retainingring and the inner annular wall have complementary snap engagementelements.
 5. The lid as defined in claim 1 wherein the material for themounting member is selected for its structural properties to mount onthe manifold and the material for the cone is selected for wearresistance.
 6. The lid as defined in claim 1 wherein the material forthe mounting member is rigid injection moldable material.
 7. The lid asdefined in claim 6 wherein the material for the mounting member is aglass reinforced nylon.
 8. The lid as defined in claim 1 wherein thematerial for the lid is selected from the group of thermoset elastomerand thermoplastic elastomer.
 9. The lid as defined in claim 1 whereinthe material for the lid is EPDM with UV stabilizers.